Explosion pressures release fastener

ABSTRACT

An explosion release fastener for releasably securing wall elements, such as, facing sheets or double-skin panels, to a building structural framework. In the event of an explosion within the building, an exteriorly presented deformable washer is forced over the fastener head thereby releasing the wall element. Means is provided for maintaining the fastener receiving opening in the wall element concentrically aligned with the fastener head to facilitate release of the wall element.

Unite States Patent 1191 Vezmar Aug. 13, 1974 [54] EXPLOSION PRESSURES RELEASE 2,76l,347 9/1956 McKee 85/ 1 JP FASTENER 3,566,738 3/l97l Cupit 85/] JP 3,585,894 6/l97l Brown 85/l JP [75] Inventor: Ale n er Velmar, Leetsdale, 3,714,747 2/1973 Curran 52/595 P a v FORElGN PATENTS OR APPLICATIONS [73] Asslgneei Robertsm Company 643,995 10 1950 Great Britain 52/521 Plttsburghi Pa. 1,168,743 9/1958 France 85/] JP [22] Filed: Feb. 14, 1973 Primary Examinerl-lenry C. Sutherland [21] Appl' 332,406 Assistant Examiner-.lames L. Ridgill, Jr.

Related A li ti n Data Attorney, Agent, or FirmHarry B. Keck; George E.

ManiaS 52 us. 01 52/1, 52/483, 52/232, ABSTRACT An explosion release fastener for releasably securing f E04c /Q F161) 35/04 wall elements, such as, facing sheets or double-skin Field of Search 595, panels, to a building structural framework. In the 50, 70 event of an explosion within the building, an exteriorly presented deformable washer is forced over the fasl References Cited tener head thereby releasing the wall element. Means UNITED STATES PATENTS is provided for maintaining the fastener receiving 734,829 7 1903 Diaz 52/483 opfining the Wall element concentrically aligned 2,007,179 7/1935 Bullis 85/] JP with the fastener head to facilitate release of the wall 2,020,767 1 1/1935 Bullis Ct al. 85/1 JP element. 2,030,088 2/1936 Young 85/l JP 2,731,065 1/1956 Powers 85/1 JP 6 Glam, 8 Drawmg Fgures PAIENIEU we 1 31974 SHEET 1 0F 2 FIG. 2- PRIOR ART PAIENR we 1 3mm sum 2 a; 2

FIG. 5

FIG.'6

FIG.8-

EXPLOSION PRESSURES RELEASE FASTENER CROSS-REFERENCES TO RELATED APPLICA- TIONS (IF ANY) This is a continuation-in-part of copending application Ser. No. 96,424 filed Dec. 9, 1970, now abandoned, and assigned to the assignee of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to pressure release fasteners, and more particularly to an improved pressure release fastener and the improved blowout wall assembly produced therefrom.

2. Description of the Prior Art A pressure release fastener is known which consists of a sheet metal fastener and a metal washer having a resilient gasket secured thereto. Such a fastener is employed to secure a facing sheet to the structural framework of a building, with the metal washer presented externally of the building. The fastener extends through an opening provided in the facing sheet the facing sheet opening having an inside diameter in excess of the outside diameter of the fastener head.

When the interior face of the facing sheet is subjected to explosive forces, the metal washer deforms and passes over the fastener head the fastener remaining in place. Simultaneously, the facing sheet is released and is moved outwardly by the explosive forces, thereby venting the explosive pressures within the building.

Heretofore, the facing sheet opening has exhibited a tendency to become misaligned with respect to the fastener head. Such misalignment may occur during the installation of the panel, and as a result of thermal expansion or contraction of the facing sheet. As a consequence of this misalignment, release of the facing sheet at a preselected elevated pressure has not always been reliable.

SUMMARY OF THE INVENTION The principal object of this invention is to provide an improved pressure release fastener and an improved blowout wall structure produced therefrom.

A further object of this invention is to provide an improved pressure release fastener having a centering element for maintaining the wall element opening aligned with the fastener head.

Still another object of this invention is to provide a pressure release fastener which cannot be over driven during installation premature deformation of the deformable metal washer being avoided.

In accordance with the present invention, a rigid spacer member, in the form of a centrally apertured plate or a sleeve member, is provided on the threaded shank in confronting relation with the resilient gasket. The rigid spacer member has an outer diameter in excess of the outer diameter of the screw head.

The wall elements may comprise facing sheets of any desired profile. In this instance, the rigid spacer member comprises a centrally apertured plate having a thickness comparable to the maximum thickness of the material from which the facing sheets may be formed.

The wall elements also may comprise double-skin insulated wall panels. In this instance, the spacer member comprises a rigid centering sleeve member having a thickness or longitudinal length comparable to the thickness of that region of the wall panel through which the present pressure release fastener extends.

The rigid spacer member provides vertical support for the wall elements and centers the wall element opening with respect to the screw head. The rigid spacer member precludes undesirable premature deformation of the deformable metal washer by excessive torque applied to the fastener.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary isometric view of a wall structure incorporating pressure release fasteners;

FIG. 2 is a cross-sectional view taken along the line 22 of FIG. 1 illustrating the installed position of a prior art pressure release fastener;

FIG. 3 is an isometric view of the present pressure release fastener;

FIG. 4 is a cross-sectional view, similar to FIG. 2, illustrating the installed position of the pressure release fastener of FIG. 3',

FIG. 5 is an isometric view illustrating an alternative embodiment of the pressure release fastener of this invention;

FIG. 6 is a cross-sectional view taken transversely of a joint between building wall panels, illustrating the installed position of the pressure release fastener of FIG.

FIG. 7 is a fragmentary cross-sectional view, illustrating a portion of the wall panel of FIG. 6 provided with an opening for receiving the pressure release fastener of FIG. 5; and

FIG. 8 is a fragmentary cross-sectional view taken transversely through a building wall panel, illustrating the installed position of the pressure release fastener of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S) Blowout Wall Assembly FIG. 1 illustrates a wall structure 10 secured to the structural framework 11 of which only horizontal girts '12 are visible. The wall structure 10 consists of a plurality of facing sheets 13 of any desired profile, secured to the girts 12 by pressure release fasteners 14. The fasteners l4 resist disengagement of the facing sheets 13 from the girt members 12 under normal wind loading. However, in the event of an explosion within the building, the fasteners 14 will release the panels 13 thereby to vent the explosion pressures within the building.

Prior Art.

FIG. 2 illustrates the installation of a prior art fastener 14A. The fastener 14A comprises a sheet metal screw 15 having a threaded shank l6 threadedly engaged in the girt l2 and a screw head 17 having an outer diameter indicated at 18. A deformable washer 19 engages the screw head 17. A resilient gasket 20 is compressed between the deformable washer l9 and the facing sheet 13. The facing sheet 13 is provided with a facing sheet opening 21 positioned immediately adjacent to the resilient gasket 20. The opening 21 has an inside diameter indicated at 22 which is greater than the outer diameter 18 of the fastener head 17. When the sheet 13 is subjected to explosive forces indicated by the arrow F, the deformable washer 19 is deformed and passes over the fastener head 17. Simultaneously,

the sheet 13 is released and passes over the fastener head 17 as the facing sheet 13 moves outwardly away from the girt 12.

It should be readily apparent that the facing sheet opening 21 may become misaligned with the fastener head 17 during installation of the fastener 15. Misalignment also may result from thermal expansion and contraction of the facing sheet 13. When misalignment oc curs, the facing sheet 13 cannot be reliably released at a selected elevated pressure.

It will also be observed in FIG. 2 that an annular space 25 is presented between the facing sheet opening 21 and the threaded shank 16. Where excessive torque is applied to the fastener 15, a portion of the resilient gasket is readily displaced axially into the annular space with the result that the deformable metal washer 19 may be prematurely deformed.

Present Improvement In accordance with the present invention, the fastener 148 (FIG. 3) is provided with a rigid spacer member 23 consisting of a centrally apertured plate which is received on the threaded shank 16. The rigid spacer member 23 preferably is formed from metal, e.g., steel, brass. Alternatively, the rigid spacer member 23 may, instead, be formed from other materials, e.g., plastics, capable of supporting concentrated loads. The rigid spacer member 23 has a thickness indicated at 24 which is comparable to the maximum thickness of the material from which the facing sheets 13 may be formed. Moreover, the deformable washer 19 is provided with a resilient gasket 20a which may have a thickness greater than that of the resilient gasket 20 (FIG. 2). If desired, the rigid spacer member 23 may be temporarily secured to the gasket 20a by any suitable means, such as a contact adhesive.

FIG. 4 illustrates the installation of the present pressure release fastener 148. It will be observed that the rigid spacer member 23 resides within the facing sheet opening 21 essentially entirely filling the annular space 25 and is clamped between the girt and the resilient gasket 20a. It will be observed that the resilient gasket 20a deforms about the peripheral edge of the rigid spacer member 23 into firm clamping engagement with the facing sheet 13.

In accordance with the present invention, axial displacement of the resilient gasket 20a by excessive torque is avoided. In the absence of axial displacement of the resilient gasket 20a, premature deformation of the metal washer I9 is essentially avoided.

The present pressure release fastener may also be used to secure wall panels of the double-skin insulated type. FIG. 5 illustrates a pressure release fastener 14C wherein a rigid centering sleeve member 26 is carried by the threaded shank 16. The sleeve member 26 has opposite end faces 27a, 27b the end face 27a being disposed in confronting relation with the resilient gasket 20a. The sleeve member 26 has a thickness or longitudinal length 28 which is comparable with the thickness of that portion ofa wall panel which is to be releasably secured to a building framework. It will be observed in FIG. 5 that the sleeve member 26 has an outer diameter 260 which is (a) greater than that of the fastener head 17, and (b) less than that of the deformable metal washer 19.

FIG. 6 illustrates a joint 29 formed between adjacent wall panels 30A, 30B of a wall structure 31, and wherein the wall panel 30A presents a panel portion 32 which is secured to a girt 33 of a building framework,

by the pressure release fastener 14C. In the illustrated arrangement, each of the wall panels 30 comprises an outer facing sheet 34, a liner sheet 35, and an insulating core 36, such as, polyurethane. As illustrated in FIG. 7, the panel portion 32 is prepared to receive the pressure release fastener 14C by providing a wall panel opening 37 which includes a recess or opening 38 in the facing sheet 34; and an enlarged opening 39 in the core 36; and an opening 40 in the liner sheet 35. Recesses 54 (only one visible) are provided in the insulating core 36 on opposite sides of the wall panel opening 37 to receive a clip member as will be described.

A clip or angle member 41 cooperates with the fastener 14C to secure the panel 30A to the girt 33. The clip member 41 includes a first arm 42 which overlies the facing sheet 34 and a second arm 43 which extends through the core opening 39 and the recesses 54. The second arm 43 engages the liner sheet 35. The first arm 42 is provided with an opening 44 for receiving the sleeve member 26. The fastener 14C and the clip member 41 cooperate to provide a positive connection between the facing and liner sheets 34, 35, and to positively secure the liner sheet 35 to the girt 33.-

It will be appreciated that the diameters of the liner sheet opening 40 and the clip member opening 44 are substantially equal to that of the centering sleeve member 26, whereby the wall panel opening 37 is aligned concentrically with the fastener head 17. The diameters of the facing sheet opening 38 and the insulating core opening 39 (FIG. 7) preferably are slightly greater than that of the centering sleeve member 26 so as not to interfere with the outward movement of the wall panels 30 away from the girt 33.

It will be observed in FIG. 6 that the centering sleeve member 26 resides within the wall panel opening 37. The centering sleeve member 26 essentially entirely fills the annular spaces defined by the threaded shank l6 and the perimeters of the liner sheet opening 40 and the clip member opening 44. The joint 29 of FIG. 6 is rendered essentially weatherproof by the seals 45. Consequently, the resilient gasket 20a (FIG. 5) is not required, although it may be provided. In the FIG. 6 arrangement, the thickness or longitudinal length 28 (FIG. 5) of the centering sleeve member 26 is such that the opposite end faces 27a, 27b thereof are proximate to and preferably engaged, respectively, with the deformable metal gasket 19 and the girt 33.

The pressure release fastener 14C may also be employed as an exposed fastener, in the manner illustrated in FIG. 8. In this instance, a wall panel 46 comprises a facing sheet 47, a liner sheet 48 and an insulating core 49, such as polyurethane. The wall panel 46 is provided with a wall panel opening designated generally by the numeral 50. The wall panel opening 50 includes openings 51, 52 in the facing and liner sheets 47, 48 and an enlarged opening 53 in the core 49. The facing and liner sheets opening 51, 52 have diameters substantially equal to the outer diameter 2611 (FIG. 5) of the rigid centering sleeve member 26. Since the fastener head 17 and the deformable metal washers 19 are exposed to the weather, the resilient gasket 20a is included. In this arrangement, the opposite ends 27a, 27b of the centering sleeve member 26 are engaged, respectively, with the girt 33 and the resilient gasket 20a.

It will be observed in FIGS. 4, 6 and 8 that in the presence of the rigid spacer member 23 and the centering sleeve member 26, the facing sheet and wall panel openings 21, 37 and 50 are at all times aligned concentrically with the fastener head 17. This necessary alignment is maintained even when the facing sheet 13 and the wall panels 30, 46 undergo expansion and contraction.

I claim:

1. In an explosion release fastener having a threaded shank and a fastener head, a deformable metal washer carried by said threaded shank and confronting said fastener head, and a resilient gasket on that side of said metal washer remote from said fastener head, the improvement comprising:

a rigid spacer member carried by said threaded shank in confronting relation with said resilient gasket, said rigid spacer member consisting of a centrally apertured plate having an outer diameter which is (a) greater than that of said fastener head, and (b) less than that of said deformable metal washer.

2. The improvement defined in claim 1 wherein said rigid spacer member is temporarily secured to said resilient gasket.

3. In a blowout wall assembly including at least one facing sheet spanning the distance between spacedapart girt members, and fastener means comprising explosion release fasteners for releasably securing said facing sheet to said girt members, the improvement in said fastener means comprising:

each of said fasteners including a threaded shank extending through a facing sheet opening into threaded engagement with said girt member and a fastener head presented exteriorly of said facing sheet;

a deformable metal washer carried by said threaded shank and abutting said fastener head;

a resilient gasket compressed between said deformable metal washer and said facing sheet; and

a rigid spacer member consisting of a centrally apertured plate carried by said threaded shank, said rigid spacer member residing within said facing sheet opening, providing vertical support for said facing sheet, and maintaining said facing sheet opening aligned with said fastener head, said rigid spacer member having an outer diameter which is (a) greater than that of said fastener head, and (b) less than that of said deformable washer. 4. The improvement defined in claim 3 wherein the 5 thickness of said rigid spacer member is at least equal to the thickness of said facing sheet.

5. The improvement defined in claim 3 wherein the annular space between said threaded shank and said facing sheet opening is essentially entirely filled by said rigid spacer member, whereby axial displacement of said resilient gasket and premature deformation of said deformable. washer are avoided.

6. In a blowout wall assembly including at least one wall panel spanning the distance between spaced-apart girt members, and fastener means comprising explosion release fasteners for releasably securing said wall panel to said girt members, said wall panel comprising a facing sheet, alinersheet, and an insulating core improvmm said fastener [116568 comprising: W hf-w each of said fasteners including a threaded shank extending through a wall panel opening into threaded engagement with said girt member and a fastener head presented exteriorly of said wall panel; W

a deformable metal washer carried by said threaded shank and abutting said fastener head;

a resilient gasket compressed between said deformable metal washer and said facing sheet of said I wall panel; and

a rigid centering sleeve member carried by said threaded shank and having opposite end faces, said rigid centering sleeve member residing within said wall panel opening with said opposite end faces en gaged with said resilient gasket and said gifi providing veri"5m p56t'f6r said wall panel, and maintaining said wall panel opening aligned with said fastener head, said rigid centering sleeve member having an outer diameter which is (a) greater than that of said fastener head, and (b) less than that of said deformable metal washer; 

1. In an explosion release fastener having a threaded shank and a fastener head, a deformable metal washer carried by said threaded shank and confronting said fastener head, and a resilient gasket on that side of said metal washer remote from said fastener head, the improvement comprising: a rigid spacer member carried by said threaded shank in confronting relation with said resilient gasket, said rigid spacer member consisting of a centrally apertured plate having an outer diameter which is (a) greater than that of said fastener head, and (b) less than that of said deformable metal washer.
 2. The improvement defined in claim 1 wherein said rigid spacer member is temporarily secured to said resilient gasket.
 3. In a blowout wall assembly including at least one facing sheet spanning the distance between spaced-apart girt members, and fastener means comprising explosion release fasteners for releasably securing said facing sheet to said girt members, the improvement in said fastener means comprising: each of said fasteners including a threaded shank extending through a facing sheet opening into threaded engagement with said girt member and a fastener head presented exteriorly of said facing sheet; a deformable metal washer carried by said threaded shank and abutting said fastener head; a resilient gasket compressed between said deformable metal washer and said facing sheet; and a rigid spacer member consisting of a centrally apertured plate carried by said threaded shank, said rigid spacer member residing within said facing sheet opening, providing vertical support for said facing sheet, and maintaining said facing sheet opening aligned with said fastener head, said rigid spacer member having an outer diameter which is (a) greater than that of said fastener head, and (b) less than that of said deformable washer.
 4. The improvement defined in claim 3 wherein the thickness of said rigid spacer member is at least equal to the thickness of said facing sheet.
 5. The improvement defined in claim 3 wherein the annular space between said threaded shank and said facing sheet opening is essentially entirely filled by said rigid spacer member, whereby axial displacement of said resilient gasket and premature deformation of said deformable washer are avoided.
 6. In a blowout wall assembly including at least one wall panel spanning the distance between spaced-apart girt members, and fastener means comprising explosion release fasteners for releasably securing said wall panel to said girt members, said wall panel comprising a facing sheet, a liner sheet, and an insulating core therebetween, the improvement in said fastener means comprising: each of said fasteners including a threaded shank extending through a wall panel opening into threaded engagement with said girt member and a fastener head presented exteriorly of said wall panel; a deformable metal washer carried by said threaded shank and abutting said fastener head; a resilient gasket compressed between said deformable metal washer and said facing sheet of said wall panel; and a rigid centering sleeve member carried by said threaded shank and having opposite end faces, said rigid centering sleeve member residing within said wall panel opening with said opposite end faces engaged with said resilient gasket and said girt, providing vertical support for said wall panel, and maintaining said wall panel opening aligned with said fastener head, said rigid centering sleeve member having an outer diameter which is (a) greater than that of said fastener head, and (b) less than that of said deformable metal washer. 